Add Linux support

[stMerlHin]

First, Thank you guys for bringing the agora rtc engine to flutter.

Is your feature request related to a problem? Please describe.
I am building an app and voice and video call is one of the required feature I would like to add to the app. Actually, this plugin supports iOS, Android, mac0S and Windows. I wonder if it's planned to add linux support since my app is meant to run on linux OS too.

Describe the solution you'd like
Add linux support.

Describe alternatives you've considered
This package: flutter_webrtc seems to be a good alternative.

Additional context
No additional context.

[github-actions]

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[littleGnAl]

As I know, there's no plan to support the linux at this time. I have raised a ticket internal, will update here if there's any news.